Arcane Prosthetic, +1

This item replaces a lost hand or arm, or an equivalent body part. While the prosthetic is attached, it functions identically to the part it replaces. You can detach or reattach it as an action, and it can’t be removed against your will. It detaches if you die. While the prosthetic is attached, you gain a +1 bonus to spell attack rolls and to the saving throw DCs of your spells.

Notes: Bonus: Spell Save DC, Bonus: Spell Attacks, by a spellcaster